Questions about tile-serving

Priv.-Doz. Dr. M. Weihrauch martin.weihrauch at
Thu Sep 3 03:13:22 EDT 2015

Great, now I understand. Then I'll make up my own "algorithm" about how
much upsampling I will allow. I guess, I'd be OK with 1-2%, that should
be unnoticable to the human eye.

Thanks so much for this software and your constant support!


Am 03.09.2015 um 07:30 schrieb Benjamin Gilbert:
> On 09/02/2015 04:42 PM, Dr. M. Weihrauch wrote:
>> If the openslide zoomlevel is eg only 2px bigger than the openslide
>> level, where do you set the cut off not to take the bigger openslide
>> zoom level?
> The Deep Zoom implementation in OpenSlide Python never upsamples.  For 
> example, CMU-1.svs has these downsample values:
> Level	Downsample
> 0	1
> 1	4.0001215362177929
> 2	16.000486144871171
> When OpenSlide Python is rendering the Deep Zoom level with downsample 
> 16, it will read pixels from slide level 1 and scale them.  That is 
> probably more cautious than necessary, and will have a negative impact 
> on performance.  However, I don't have a recommendation for how much 
> upsampling to allow.  Does anyone else have experience with this?
> --Benjamin Gilbert
> _______________________________________________
> openslide-users mailing list
> openslide-users at

Priv.-Doz. Dr. med. Martin Weihrauch
Facharzt für Innere Medizin,
Hämatologie und internistische Onkologie
Ärztlicher Geschäftsführer des
MVZ der Uniklinik Köln
50924 Köln
Tel: 0221-47886615
Fax: 0221-47886616

More information about the openslide-users mailing list